Such a hinge construction is generally known. Usually, the central shaft is provided with a baseplate as supporting surface. The first run-on surfaces are then realized by means of cams provided at the bottom surface of the mirror housing, while the second run-on surfaces are realized by means of cams which are provided on a baseplate of the central shaft.
The central shaft is usually fixedly attached, by way of the baseplate, to the body of the motor vehicle, so that the mirror housing in the folded-out position extends substantially transversely to the body of the motor vehicle.
By means of the hinge construction, the mirror housing can be pivoted rearwards from the folded-out position to a folded-in position, in which the mirror housing projects less far and extends in rearward direction more alongside the body.
Typically, the wing mirror unit comprises an electric drive with which the mirror housing is adjustable between the folded-in position and the folded-out position.
In the known hinge construction, the run-on surfaces cooperate against the action of a spring, and the drive is cut off by means of a cut-off circuit based on a current strength limitation when the run-on surfaces cooperate.
A disadvantage of the known hinge construction is that the bottom surface of the mirror housing and the supporting surface at the base of the central shaft can move apart in axial direction as a result of the cooperation of the run-on surfaces. In particular, this can happen as a result of deceleration when the drive is cut off. As a result, between mirror housing and supporting surface, a slit may be formed which causes wind noise. Furthermore, the support of the mirror housing may become less stable as a result, so that for instance a mirror glass carried by the mirror housing can give an undesired vibrating picture during driving. Also, the cams of the baseplate need to be able to resist a relatively high surface pressure, so that in practice, for reasons of strength, the baseplate is designed as a metal part, which is relatively costly.